Forty-eight years ago today, on Feb. 24, 1969, Johnny Cash recorded his At San Quentin album. The 10-song project, which was released on June 4, 1969, was recorded live at the San Quentin State Prison in San Quentin, Calif.

Cash first performed at San Quentin State Prison on Jan. 1, 1959. The country icon had been arrested several times, and although he never served any time in prison, he felt compassion for those who did.

“He always identified with the underdog,” Cash’s younger brother, Tommy Cash, tells the BBC. “He identified with the prisoners because many of them had served their sentences and had been rehabilitated in some cases but were still kept there the rest of their lives. He felt a great empathy with those people.”

At San Quentin includes performances of "I Walk the Line," "A Boy Named Sue," "There'll Be Peace in the Valley" and two versions of "San Quentin," repeated at the request of the audience. Cash performed both "San Quentin" and "A Boy Named Sue" for the first time while at San Quentin State Prison; the latter landed at No. 1 on the country charts and earned the now-legend his only No. 1 on the adult contemporary charts as well.

At San Quentin was certified platinum three times, for sales in excess of 3 million copies. Cash earned Best Country Vocal Performance, Male, at the Grammy Awards for "A Boy Named Sue;" additionally, he won CMA Awards for Album of the Year, for At San Quentin, and Single of the Year, for "A Boy Named Sue." Cash also won his only CMA trophy for Entertainer of the Year in 1969 as well.

At San Quentin is available for purchase on Amazon and iTunes.

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